package com.kookkai;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.json.JSONObject;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnMapClickListener;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
import com.kookkai.util.DirectionsJSONParser;

import android.graphics.Color;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.Dialog;
import android.support.v4.app.FragmentManager;
import android.util.Log;
import android.view.Menu;

public class MainActivity extends Activity implements LocationListener {
	GoogleMap mGoogleMap;
	ArrayList<LatLng> mMarkerPoints;
	double mLatitude = 0;
	double mLongitude = 0;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		int status = GooglePlayServicesUtil
				.isGooglePlayServicesAvailable(getBaseContext());
		// Showing status
		if (status != ConnectionResult.SUCCESS) { // Google Play Services are
													// not available
			int requestCode = 10;
			Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this,
					requestCode);
			dialog.show();
		} else {// Google Play Services are available
				// Initializing
			mMarkerPoints = new ArrayList<LatLng>();

			// Getting reference to SupportMapFragment of the activity_main
			MapFragment fm = (MapFragment) getFragmentManager().findFragmentById(R.id.map);

			// Getting Map for the SupportMapFragment
			mGoogleMap = fm.getMap();

			// Enable MyLocation Button in the Map
			mGoogleMap.setMyLocationEnabled(true);

			// Getting LocationManager object from System Service
			// LOCATION_SERVICE
			LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

			// Creating a criteria object to retrieve provider
			Criteria criteria = new Criteria();

			// Getting the name of the best provider
			String provider = locationManager.getBestProvider(criteria, true);

			// Getting Current Location From GPS
			Location location = locationManager.getLastKnownLocation(provider);

			if (location != null) {
				onLocationChanged(location);
			}
			locationManager.requestLocationUpdates(provider, 20000, 0, this);
			 
            // Setting onclick event listener for the map
			mGoogleMap.setOnMapClickListener(new OnMapClickListener() {
 
                @Override
                public void onMapClick(LatLng point) {
 
                    // Already map contain destination location
                    if(mMarkerPoints.size()>1){
 
                    	//FragmentManager fm = getSupportFragmentManager();
                        mMarkerPoints.clear();
                        mGoogleMap.clear();
                       
                        LatLng startPoint = new LatLng(mLatitude, mLongitude);
 
                        // draw the marker at the current position
                        drawMarker(startPoint);
                    }
 
                    // draws the marker at the currently touched location
                    drawMarker(point);
 
                    // Checks, whether start and end locations are captured
                    if(mMarkerPoints.size() >= 2){
                        LatLng origin = mMarkerPoints.get(0);
                        LatLng dest = mMarkerPoints.get(1);
 
                        // Getting URL to the Google Directions API
                        String url = getDirectionsUrl(origin, dest);
 
                        DownloadTask downloadTask = new DownloadTask();
 
                        // Start downloading json data from Google Directions API
                        downloadTask.execute(url);
                    }
                }

				
            });
		}
	}

	private String getDirectionsUrl(LatLng origin, LatLng dest) {
		// Origin of route
        String str_origin = "origin="+origin.latitude+","+origin.longitude;
 
        // Destination of route
        String str_dest = "destination="+dest.latitude+","+dest.longitude;
 
        // Sensor enabled
        String sensor = "sensor=false";
 
        // Building the parameters to the web service
        String parameters = str_origin+"&"+str_dest+"&"+sensor;
 
        // Output format
        String output = "json";
 
        // Building the url to the web service
        String url = "https://maps.googleapis.com/maps/api/directions/"+output+"?"+parameters;
 
        return url;
	}

	private void drawMarker(LatLng point) {
		mMarkerPoints.add(point);
		 
        // Creating MarkerOptions
        MarkerOptions options = new MarkerOptions();
 
        // Setting the position of the marker
        options.position(point);
 
        /**
        * For the start location, the color of marker is GREEN and
        * for the end location, the color of marker is RED.
        */
        if(mMarkerPoints.size()==1){
            options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
        }else if(mMarkerPoints.size()==2){
            options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
        }
 
        // Add new marker to the Google Map Android API V2
        mGoogleMap.addMarker(options);
	}
	/** A method to download json data from url */
    private String downloadUrl(String strUrl) throws IOException{
        String data = "";
        InputStream iStream = null;
        HttpURLConnection urlConnection = null;
        try{
            URL url = new URL(strUrl);
 
            // Creating an http connection to communicate with url
            urlConnection = (HttpURLConnection) url.openConnection();
 
            // Connecting to url
            urlConnection.connect();
 
            // Reading data from url
            iStream = urlConnection.getInputStream();
 
            BufferedReader br = new BufferedReader(new InputStreamReader(iStream));
 
            StringBuffer sb  = new StringBuffer();
 
            String line = "";
            while( ( line = br.readLine())  != null){
                sb.append(line);
            }
 
            data = sb.toString();
 
            br.close();
 
        }catch(Exception e){
            Log.d("Exception while downloading url", e.toString());
        }finally{
            iStream.close();
            urlConnection.disconnect();
        }
        return data;
    }

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

	@Override
	public void onLocationChanged(Location location) {
		// Draw the marker, if destination location is not set
        if(mMarkerPoints.size() < 2){
 
            mLatitude = location.getLatitude();
            mLongitude = location.getLongitude();
            LatLng point = new LatLng(mLatitude, mLongitude);
 
            mGoogleMap.moveCamera(CameraUpdateFactory.newLatLng(point));
            mGoogleMap.animateCamera(CameraUpdateFactory.zoomTo(12));
 
            drawMarker(point);
        }
	}

	@Override
	public void onProviderDisabled(String arg0) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void onProviderEnabled(String arg0) {
		// TODO Auto-generated method stub
		
	}

	@Override
	public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
		// TODO Auto-generated method stub
		
	}
	
	/** A class to download data from Google Directions URL */
    private class DownloadTask extends AsyncTask<String, Void, String>{
 
        // Downloading data in non-ui thread
        @Override
        protected String doInBackground(String... url) {
 
            // For storing data from web service
            String data = "";
 
            try{
                // Fetching the data from web service
                data = downloadUrl(url[0]);
            }catch(Exception e){
                Log.d("Background Task",e.toString());
            }
            return data;
        }
 
        // Executes in UI thread, after the execution of
        // doInBackground()
        @Override
        protected void onPostExecute(String result) {
            super.onPostExecute(result);
 
            ParserTask parserTask = new ParserTask();
 
            // Invokes the thread for parsing the JSON data
            parserTask.execute(result);
        }
    }
    /** A class to parse the Google Directions in JSON format */
    private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String,String>>> >{
 
        // Parsing the data in non-ui thread
        @Override
        protected List<List<HashMap<String, String>>> doInBackground(String... jsonData) {
 
            JSONObject jObject;
            List<List<HashMap<String, String>>> routes = null;
 
            try{
                jObject = new JSONObject(jsonData[0]);
                DirectionsJSONParser parser = new DirectionsJSONParser();
 
                // Starts parsing data
                routes = parser.parse(jObject);
            }catch(Exception e){
                e.printStackTrace();
            }
            return routes;
        }
 
        // Executes in UI thread, after the parsing process
        @Override
        protected void onPostExecute(List<List<HashMap<String, String>>> result) {
            ArrayList<LatLng> points = null;
            PolylineOptions lineOptions = null;
 
            // Traversing through all the routes
            for(int i=0;i<result.size();i++){
                points = new ArrayList<LatLng>();
                lineOptions = new PolylineOptions();
 
                // Fetching i-th route
                List<HashMap<String, String>> path = result.get(i);
 
                // Fetching all the points in i-th route
                for(int j=0;j<path.size();j++){
                    HashMap<String,String> point = path.get(j);
 
                    double lat = Double.parseDouble(point.get("lat"));
                    double lng = Double.parseDouble(point.get("lng"));
                    LatLng position = new LatLng(lat, lng);
 
                    points.add(position);
                }
 
                // Adding all the points in the route to LineOptions
                lineOptions.addAll(points);
                lineOptions.width(2);
                lineOptions.color(Color.RED);
            }
 
            // Drawing polyline in the Google Map for the i-th route
            mGoogleMap.addPolyline(lineOptions);
        }
    }

}
